Methods for service slice selection and separation

ABSTRACT

Embodiments include methods and apparatuses for providing access to a network slice in a communication system. In an embodiment, a network server that implements a Control Plane (CP) Network Function (NF) may receive a Non-Access Stratum (NAS) message from a wireless transmit and receive unit (WTRU). The NAS message comprises a Mobility Management (MM) message for registration and a Session Management (SM) messages for a specific service provided by the network slice. After selecting the network slice, the network server may transmit the SM message to another CP NF in the network slice to establish a communication link between the WTRU and the network slice.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Stage, under 35 U.S.C. § 371, ofInternational Application No. PCT/US2017/025603 filed Mar. 31, 2017,which claims the benefit of U.S. Provisional Application No. 62/317,167,filed on Apr. 1, 2016 and U.S. Provisional Application No. 62/337,085,filed on May 16, 2016, the contents of which are hereby incorporated byreference herein.

BACKGROUND

Studies by the 3rd Generation Partnership Project (3GPP) on thedevelopment of a fifth generation (5G) wireless communication systemhave shown network slicing to be an important feature of the 5G systemsand an enabler for providing different services and meeting differentservice requirements. Network slicing may be performed by groupingdifferent network entities into a logical network, such as sharednetwork functions and dedicated network functions, which may belogically or physically isolated from each other. For example, a networkslice may include a logical connection of shared network functionsresiding in various nodes of a wireless communication system and mayallow a user to obtain dedicated services or network capacity on a perservice basis. Thus, it would be desirable to have a method andapparatus configured to support these network functions using networkslicing.

SUMMARY

In an embodiment, a method for providing access to a network slice inwireless communications is disclosed. The method may include: receiving,at a shared Control Plane (CP) Network Function (NF), a Non-AccessStratum (NAS) message that comprises a Mobility Management (MM) messageand a Session Management (SM) message; and transmitting, to a non-sharedCP NF in the network slice, the SM message that indicates a User Plane(UP) service provided by the network slice.

In another embodiment, a network server configured to implement a sharedControl Plane (CP) Network Function (NF) for providing access to anetwork slice in wireless communications is disclosed. The networkserver may include: a processor configured to receive, at the shared CPNF, a Non-Access Stratum (NAS) message that comprises a MobilityManagement (MM) message and a Session Management (SM) message; andtransmit, to a non-shared CP NF in the network slice, the SM messagethat indicates a User Plane (UP) service provided by the network slice.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding may be had from the following description,given by way of example in conjunction with the accompanying drawingswherein:

FIG. 1A is a system diagram of an example communications system in whichone or more disclosed embodiments may be implemented;

FIG. 1B is a system diagram of an example wireless transmit/receive unit(WTRU) that may be used within the communications system illustrated inFIG. 1A;

FIG. 1C is a system diagram of an example radio access network and anexample core network that may be used within the communications systemillustrated in FIG. 1A;

FIG. 2A is a diagram illustrating network slice instances that aregrouped by independent Control Plane (CP) and User Plane (UP) nodes pernetwork slices;

FIG. 2B is a diagram illustrating network slice instances that aregrouped by shared Control Plane (CP) nodes and partly independentControl Plane (CP) and completely independent User Plane (UP) nodes pernetwork slices;

FIG. 2C is a diagram illustrating network slice instances that aregrouped by shared Control Plane (CP) and independent User Plane (UP)nodes per network slices;

FIG. 3 is a diagram illustrating an example network slicing thatincludes a shared CP node and independent UP nodes;

FIG. 4 is a diagram illustrating an example of network slice selectionper service offered by a network;

FIG. 5 is a diagram illustrating an example of network slice selectionbased on a multi-dimensional descriptor;

FIG. 6 is a diagram illustrating overall architecture for networkslicing per data types;

FIG. 7A is a signaling diagram illustrating a slice selection forservice supported by the network slice;

FIG. 7B is a continuation of FIG. 7A;

FIG. 8 is a signaling diagram illustrating a dedicated slice selectionat a shared CP node;

FIG. 9 is a signaling diagram illustrating a delayed network sliceselection during session management procedure; and

FIG. 10 is a diagram illustrating an example procedure for providingaccess to a dedicate network slice in a shared CP network function (NF).

DETAILED DESCRIPTION

FIG. 1A is a diagram of an example communications system 100 in whichone or more disclosed embodiments may be implemented. The communicationssystem 100 may be a multiple access system that provides content, suchas voice, data, video, messaging, broadcast, etc., to multiple wirelessusers. The communications system 100 may enable multiple wireless usersto access such content through the sharing of system resources,including wireless bandwidth. For example, the communications systems100 may employ one or more channel access methods, such as code divisionmultiple access (CDMA), time division multiple access (TDMA), frequencydivision multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrierFDMA (SC-FDMA), and the like.

As shown in FIG. 1A, the communications system 100 may include wirelesstransmit/receive units (WTRUs) 102 a, 102 b, 102 c, 102 d, a radioaccess network (RAN) 104, a core network 106, a public switchedtelephone network (PSTN) 108, the Internet 110, and other networks 112,though it will be appreciated that the disclosed embodiments contemplateany number of WTRUs, base stations, networks, and/or network elements.Each of the WTRUs 102 a, 102 b, 102 c, 102 d may be any type of deviceconfigured to operate and/or communicate in a wireless environment. Byway of example, the WTRUs 102 a, 102 b, 102 c, 102 d may be configuredto transmit and/or receive wireless signals and may include userequipment (UE), a mobile station, a fixed or mobile subscriber unit, apager, a cellular telephone, a personal digital assistant (PDA), asmartphone, a laptop, a netbook, a personal computer, a wireless sensor,consumer electronics, and the like.

The communications systems 100 may also include a base station 114 a anda base station 114 b. Each of the base stations 114 a, 114 b may be anytype of device configured to wirelessly interface with at least one ofthe WTRUs 102 a, 102 b, 102 c, 102 d to facilitate access to one or morecommunication networks, such as the core network 106, the Internet 110,and/or the other networks 112. By way of example, the base stations 114a, 114 b may be a base transceiver station (BTS), a Node-B, an eNode B,a Home Node B, a Home eNode B, a site controller, an access point (AP),a wireless router, and the like. While the base stations 114 a, 114 bare each depicted as a single element, it will be appreciated that thebase stations 114 a, 114 b may include any number of interconnected basestations and/or network elements.

The base station 114 a may be part of the RAN 104, which may alsoinclude other base stations and/or network elements (not shown), such asa base station controller (BSC), a radio network controller (RNC), relaynodes, etc. The base station 114 a and/or the base station 114 b may beconfigured to transmit and/or receive wireless signals within aparticular geographic region, which may be referred to as a cell (notshown). The cell may further be divided into cell sectors. For example,the cell associated with the base station 114 a may be divided intothree sectors. Thus, in one embodiment, the base station 114 a mayinclude three transceivers, i.e., one for each sector of the cell. Inanother embodiment, the base station 114 a may employ multiple-inputmultiple-output (MIMO) technology and, therefore, may utilize multipletransceivers for each sector of the cell.

The base stations 114 a, 114 b may communicate with one or more of theWTRUs 102 a, 102 b, 102 c, 102 d over an air interface 116, which may beany suitable wireless communication link (e.g., radio frequency (RF),microwave, infrared (IR), ultraviolet (UV), visible light, etc.). Theair interface 116 may be established using any suitable radio accesstechnology (RAT).

More specifically, as noted above, the communications system 100 may bea multiple access system and may employ one or more channel accessschemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. Forexample, the base station 114 a in the RAN 104 and the WTRUs 102 a, 102b, 102 c may implement a radio technology such as Universal MobileTelecommunications System (UMTS) Terrestrial Radio Access (UTRA), whichmay establish the air interface 116 using wideband CDMA (WCDMA). WCDMAmay include communication protocols such as High-Speed Packet Access(HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed DownlinkPacket Access (HSDPA) and/or High-Speed Uplink Packet Access (HSUPA).

In another embodiment, the base station 114 a and the WTRUs 102 a, 102b, 102 c may implement a radio technology such as Evolved UMTSTerrestrial Radio Access (E-UTRA), which may establish the air interface116 using Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A).

In other embodiments, the base station 114 a and the WTRUs 102 a, 102 b,102 c may implement radio technologies such as IEEE 802.16 (i.e.,Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000,CDMA2000 1×, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), InterimStandard 95 (IS-95), Interim Standard 856 (IS-856), Global System forMobile communications (GSM), Enhanced Data rates for GSM Evolution(EDGE), GSM EDGE (GERAN), and the like.

The base station 114 b in FIG. 1A may be a wireless router, Home Node B,Home eNode B, or access point, for example, and may utilize any suitableRAT for facilitating wireless connectivity in a localized area, such asa place of business, a home, a vehicle, a campus, and the like. In oneembodiment, the base station 114 b and the WTRUs 102 c, 102 d mayimplement a radio technology such as IEEE 802.11 to establish a wirelesslocal area network (WLAN). In another embodiment, the base station 114 band the WTRUs 102 c, 102 d may implement a radio technology such as IEEE802.15 to establish a wireless personal area network (WPAN). In yetanother embodiment, the base station 114 b and the WTRUs 102 c, 102 dmay utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE,LTE-A, etc.) to establish a picocell or femtocell. As shown in FIG. 1A,the base station 114 b may have a direct connection to the Internet 110.Thus, the base station 114 b may not be required to access the Internet110 via the core network 106.

The RAN 104 may be in communication with the core network 106, which maybe any type of network configured to provide voice, data, applications,and/or voice over internet protocol (VoIP) services to one or more ofthe WTRUs 102 a, 102 b, 102 c, 102 d. For example, the core network 106may provide call control, billing services, mobile location-basedservices, pre-paid calling, Internet connectivity, video distribution,etc., and/or perform high-level security functions, such as userauthentication. Although not shown in FIG. 1A, it will be appreciatedthat the RAN 104 and/or the core network 106 may be in direct orindirect communication with other RANs that employ the same RAT as theRAN 104 or a different RAT. For example, in addition to being connectedto the RAN 104, which may be utilizing an E-UTRA radio technology, thecore network 106 may also be in communication with another RAN (notshown) employing a GSM radio technology.

The core network 106 may also serve as a gateway for the WTRUs 102 a,102 b, 102 c, 102 d to access the PSTN 108, the Internet 110, and/orother networks 112. The PSTN 108 may include circuit-switched telephonenetworks that provide plain old telephone service (POTS). The Internet110 may include a global system of interconnected computer networks anddevices that use common communication protocols, such as thetransmission control protocol (TCP), user datagram protocol (UDP) andthe internet protocol (IP) in the TCP/IP internet protocol suite. Thenetworks 112 may include wired or wireless communications networks ownedand/or operated by other service providers. For example, the networks112 may include another core network connected to one or more RANs,which may employ the same RAT as the RAN 104 or a different RAT.

Some or all of the WTRUs 102 a, 102 b, 102 c, 102 d in thecommunications system 100 may include multi-mode capabilities, i.e., theWTRUs 102 a, 102 b, 102 c, 102 d may include multiple transceivers forcommunicating with different wireless networks over different wirelesslinks. For example, the WTRU 102 c shown in FIG. 1A may be configured tocommunicate with the base station 114 a, which may employ acellular-based radio technology, and with the base station 114 b, whichmay employ an IEEE 802 radio technology.

FIG. 1B is a system diagram of an example WTRU 102. As shown in FIG. 1B,the WTRU 102 may include a processor 118, a transceiver 120, atransmit/receive element 122, a speaker/microphone 124, a keypad 126, adisplay/touchpad 128, non-removable memory 130, removable memory 132, apower source 134, a global positioning system (GPS) chipset 136, andother peripherals 138. It will be appreciated that the WTRU 102 mayinclude any sub-combination of the foregoing elements while remainingconsistent with an embodiment.

The processor 118 may be a general purpose processor, a special purposeprocessor, a conventional processor, a digital signal processor (DSP), aplurality of microprocessors, one or more microprocessors in associationwith a DSP core, a controller, a microcontroller, Application SpecificIntegrated Circuits (ASICs), Field Programmable Gate Array (FPGAs)circuits, any other type of integrated circuit (IC), a state machine,and the like. The processor 118 may perform signal coding, dataprocessing, power control, input/output processing, and/or any otherfunctionality that enables the WTRU 102 to operate in a wirelessenvironment. The processor 118 may be coupled to the transceiver 120,which may be coupled to the transmit/receive element 122. While FIG. 1Bdepicts the processor 118 and the transceiver 120 as separatecomponents, it will be appreciated that the processor 118 and thetransceiver 120 may be integrated together in an electronic package orchip.

The transmit/receive element 122 may be configured to transmit signalsto, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, thetransmit/receive element 122 may be an antenna configured to transmitand/or receive RF signals. In another embodiment, the transmit/receiveelement 122 may be an emitter/detector configured to transmit and/orreceive IR, UV, or visible light signals, for example. In yet anotherembodiment, the transmit/receive element 122 may be configured totransmit and receive both RF and light signals. It will be appreciatedthat the transmit/receive element 122 may be configured to transmitand/or receive any combination of wireless signals.

In addition, although the transmit/receive element 122 is depicted inFIG. 1B as a single element, the WTRU 102 may include any number oftransmit/receive elements 122. More specifically, the WTRU 102 mayemploy MIMO technology. Thus, in one embodiment, the WTRU 102 mayinclude two or more transmit/receive elements 122 (e.g., multipleantennas) for transmitting and receiving wireless signals over the airinterface 116.

The transceiver 120 may be configured to modulate the signals that areto be transmitted by the transmit/receive element 122 and to demodulatethe signals that are received by the transmit/receive element 122. Asnoted above, the WTRU 102 may have multi-mode capabilities. Thus, thetransceiver 120 may include multiple transceivers for enabling the WTRU102 to communicate via multiple RATs, such as UTRA and IEEE 802.11, forexample.

The processor 118 of the WTRU 102 may be coupled to, and may receiveuser input data from, the speaker/microphone 124, the keypad 126, and/orthe display/touchpad 128 (e.g., a liquid crystal display (LCD) displayunit or organic light-emitting diode (OLED) display unit). The processor118 may also output user data to the speaker/microphone 124, the keypad126, and/or the display/touchpad 128. In addition, the processor 118 mayaccess information from, and store data in, any type of suitable memory,such as the non-removable memory 130 and/or the removable memory 132.The non-removable memory 130 may include random-access memory (RAM),read-only memory (ROM), a hard disk, or any other type of memory storagedevice. The removable memory 132 may include a subscriber identitymodule (SIM) card, a memory stick, a secure digital (SD) memory card,and the like. In other embodiments, the processor 118 may accessinformation from, and store data in, memory that is not physicallylocated on the WTRU 102, such as on a server or a home computer (notshown).

The processor 118 may receive power from the power source 134, and maybe configured to distribute and/or control the power to the othercomponents in the WTRU 102. The power source 134 may be any suitabledevice for powering the WTRU 102. For example, the power source 134 mayinclude one or more dry cell batteries (e.g., nickel-cadmium (NiCd),nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion),etc.), solar cells, fuel cells, and the like.

The processor 118 may also be coupled to the GPS chipset 136, which maybe configured to provide location information (e.g., longitude andlatitude) regarding the current location of the WTRU 102. In additionto, or in lieu of, the information from the GPS chipset 136, the WTRU102 may receive location information over the air interface 116 from abase station (e.g., base stations 114 a, 114 b) and/or determine itslocation based on the timing of the signals being received from two ormore nearby base stations. It will be appreciated that the WTRU 102 mayacquire location information by way of any suitablelocation-determination method while remaining consistent with anembodiment.

The processor 118 may further be coupled to other peripherals 138, whichmay include one or more software and/or hardware modules that provideadditional features, functionality and/or wired or wirelessconnectivity. For example, the peripherals 138 may include anaccelerometer, an e-compass, a satellite transceiver, a digital camera(for photographs or video), a universal serial bus (USB) port, avibration device, a television transceiver, a hands free headset, aBluetooth® module, a frequency modulated (FM) radio unit, a digitalmusic player, a media player, a video game player module, an Internetbrowser, and the like.

FIG. 1C is a system diagram of the RAN 104 and the core network 106according to an embodiment. As noted above, the RAN 104 may employ anE-UTRA radio technology to communicate with the WTRUs 102 a, 102 b, 102c over the air interface 116. The RAN 104 may also be in communicationwith the core network 106.

The RAN 104 may include eNode-Bs 140 a, 140 b, 140 c, though it will beappreciated that the RAN 104 may include any number of eNode-Bs whileremaining consistent with an embodiment. The eNode-Bs 140 a, 140 b, 140c may each include one or more transceivers for communicating with theWTRUs 102 a, 102 b, 102 c over the air interface 116. In one embodiment,the eNode-Bs 140 a, 140 b, 140 c may implement MIMO technology. Thus,the eNode-B 140 a, for example, may use multiple antennas to transmitwireless signals to, and receive wireless signals from, the WTRU 102 a.

Each of the eNode-Bs 140 a, 140 b, 140 c may be associated with aparticular cell (not shown) and may be configured to handle radioresource management decisions, handover decisions, scheduling of usersin the uplink and/or downlink, and the like. As shown in FIG. 1C, theeNode-Bs 140 a, 140 b, 140 c may communicate with one another over an X2interface.

The core network 106 shown in FIG. 1C may include a mobility managemententity gateway (MME) 142, a serving gateway 144, and a packet datanetwork (PDN) gateway 146. While each of the foregoing elements aredepicted as part of the core network 106, it will be appreciated thatany one of these elements may be owned and/or operated by an entityother than the core network operator.

The MME 142 may be connected to each of the eNode-Bs 140 a, 140 b, 140 cin the RAN 104 via an Si interface and may serve as a control node. Forexample, the MME 142 may be responsible for authenticating users of theWTRUs 102 a, 102 b, 102 c, bearer activation/deactivation, selecting aparticular serving gateway during an initial attach of the WTRUs 102 a,102 b, 102 c, and the like. The MME 142 may also provide a control planefunction for switching between the RAN 104 and other RANs (not shown)that employ other radio technologies, such as GSM or WCDMA.

The serving gateway 144 may be connected to each of the eNode Bs 140 a,140 b, 140 c in the RAN 104 via the Si interface. The serving gateway144 may generally route and forward user data packets to/from the WTRUs102 a, 102 b, 102 c. The serving gateway 144 may also perform otherfunctions, such as anchoring user planes during inter-eNode B handovers,triggering paging when downlink data is available for the WTRUs 102 a,102 b, 102 c, managing and storing contexts of the WTRUs 102 a, 102 b,102 c, and the like.

The serving gateway 144 may also be connected to the PDN gateway 146,which may provide the WTRUs 102 a, 102 b, 102 c with access topacket-switched networks, such as the Internet 110, to facilitatecommunications between the WTRUs 102 a, 102 b, 102 c and IP-enableddevices.

The core network 106 may facilitate communications with other networks.For example, the core network 106 may provide the WTRUs 102 a, 102 b,102 c with access to circuit-switched networks, such as the PSTN 108, tofacilitate communications between the WTRUs 102 a, 102 b, 102 c andtraditional land-line communications devices. For example, the corenetwork 106 may include, or may communicate with, an IP gateway (e.g.,an IP multimedia subsystem (IMS) server) that serves as an interfacebetween the core network 106 and the PSTN 108. In addition, the corenetwork 106 may provide the WTRUs 102 a, 102 b, 102 c with access to thenetworks 112, which may include other wired or wireless networks thatare owned and/or operated by other service providers.

Other network 112 may further be connected to an IEEE 802.11 basedwireless local area network (WLAN) 160. The WLAN 160 may include anaccess router 165. The access router may contain gateway functionality.The access router 165 may be in communication with a plurality of accesspoints (APs) 170 a, 170 b. The communication between access router 165and APs 170 a, 170 b may be via wired Ethernet (IEEE 802.3 standards),or any type of wireless communication protocol. AP 170 a is in wirelesscommunication over an air interface with WTRU 102 d.

Referring now to FIGS. 2A, 2B, and 2C, network slice instances 206, 208,210, 212, 214, 218, 220, 222 which are grouped by control plane (CP) anduser plane (UP) nodes per network slice are shown. A network slice mayhave independent CP 203, 207 and UP nodes 205, 209 as shown in FIG. 2A.Specifically, the CN Instance #1 206 may include a CP node 203 and a UPnode 205 inside the network slice of CN Instance #1 206. Similarly, theCN Instance #2 208 may include a CP node 207 and a UP node 209 insidethe network slice of CN Instance #2 208. The CP nodes 203, 207 in the CNInstance #1 206 and the CN Instance #2 208 respectively may receivecontrol plane signaling messages from a WTRU 202. The UP nodes 205, 209in the CN Instance #1 206 and the CN Instance #2 208 respectively mayreceive user plane data from the WTRU 202. For example, the WTRU 202 maytransmit registration and authentication requests to the CP node 203 ofCN Instance #1 206. The WTRU 202 may also transmit data packets to theUP node 205 of CN Instance #1 206. Similarly, the WTRU 202 may transmitits mobility management message to the CP node 207 of CN Instance #2 208and its session management message to the UP node 209 of CN Instance #2208. The WTRU 202 may be connected to the CN Instance #1 206 and CNInstance #2 208 via the Shared Access Network (AN) 204.

Referring now to FIG. 2B, a diagram of an embodiment where a networkslice may share a CP node 210 but have partly independent CP 211, 215and completely independent UP nodes 218, 216 per network slices isshown. Specifically, the CN Instance slice #1 212 or CN Instance slice#2 214 may share the shared core network (CN) control plane (CP)functions. The CN Instance slice #1 212 may include a partly independentCP node 211 and a completely independent UP node 218. The CN Instanceslice #2 214 may include a partly independent CP node 215 and acompletely independent UP node 216. The shared CN CP functions 210 mayperform common network functions for the CN Instance slice #1 212 and CNInstance slice #2 214. Such common network functions may includeauthentication, mobility management, session management, gatewayfunction, and the like.

The partly independent CP nodes 211, 215 may perform slice specificcontrol plane network functions. The completely independent UP nodes213, 216 may also perform slice specific user plane network functions.The WTRU 202 may be connected to the CN Instance slice #1 212 or CNInstance slice #2 214 without the shared CN CP functions 210 for a slicespecific network function. Such a slice specific network function mayinclude non-shared session management functions.

Referring now to FIG. 2C, a diagram of an embodiment where a networkslice may share control plane (CP) functions 217 in a shared CN CP node218 and have independent user plane (UP) nodes 219, 221 per networkslices is shown. The shared CN CP node 218 may perform shared controlplane functions 217 for several core network instances such as the UPInstance #1 220 and UP Instance #2 222. The UP Instance #1 220 and UPInstance #2 222 may include independent UP nodes 219, 221, respectively.The Shared CN CP 218, UP Instance #1 220, and UP Instance #2 222 may beconnected to the WTRU 202 via the shared access network (AN) 204. The UPInstance #1 220 and UP Instance #2 222 may have the shared CN CP node218 for the control plane functionalities. The shared CN CP functions217 may perform common control plane functions for the UP Instance #1220 and UP Instance #2 222. The common control plane functions performedby the shared CP functions 217 may include authentication, mobilitymanagement, gateway function, and the like. The UP nodes 219 and 221 inthe UP Instance #1 220 and UP Instance #2 222 may perform slice specificuser plane network functions such as non-shared session managementfunctions.

Referring now to FIG. 3, an example network slicing that includes sharedCP functionalities 314 and independent UP functionalities 312, 316 isshown. The network slicing in FIG. 3 may be modeled towards the networkslice instances shown in FIG. 2C. The shared CP functionalities 314 andindependent UP functionalities 312 may form a network slice (i.e. CoreNetwork Instance #1 308). Similarly, the shared CP functionalities 314and independent UP functionalities 316 may form another network slice(i.e. Core Network Instance #2 310).

As shown in FIG. 3, the Core Network Instance #1 308 may include asingle set of control plane functionalities 314 (C-Plane functions) anda single set of user plane functionalities 312 (U-Plane functions). Thesingle set of control plane functionalities 314 may include multiplefunctions such as CPF #1 320, CPF #2 322, and CPF #3 324 for the commonnetwork functions. Such common network functions may includeauthentication, mobility management, session management, gatewayfunction, and the like. The single set of user plane functionalities 312may include multiple functions such as NS-1 UPF #1 326, NS-1 UPF #2 328,and NS-1 UPF #3 330 for the slice specific user plane network functions.Similarly, the Core Network Instance #2 310 may include a single set ofcontrol plane functionalities 314 and a single set of user planefunctionalities 316. The single set of user plane functionalities 316may include multiple functions such as NS-2 UPF #1 332, NS-2 UPF #2 334,and NS-2 UPF #3 336 for the slice specific user plane network functions.

In an embodiment, the Core Network Instance #1 308 or Core NetworkInstance #2 310 may be a dedicated network slice for the WTRU 302depending on the type of WTRU 302. The type of WTRU 302 may beidentified by using specific parameters such as WTRU 302 usage type,WTRU's 302 subscription information, and the like.

A set of C-Plane functions, CPF #1 320, CPF #2 322, and CPF #3 324, maybe responsible for supporting mobility of the WTRU 302 if the mobilitymanagement is demanded by the WTRU 302. In addition, the CPF #1 320, CPF#2 322, and CPF #3 324 may be responsible for admitting the WTRU 302into the network by performing authentication and subscriptionverification. For example, the CPF #1 320 in the CP Functionalities 314may provide mobility management to the WTRU 302 for the Core NetworkInstance #1 308. At the same time, the CPF #1 in the CP Functionalities314 may provide another mobility management to the WTRU 302 for the CoreNetwork Instance #2 310. Similarly, the CPF #2 322 in the CPFunctionalities 314 may authenticate the WTRU 302 for the Core NetworkInstance #1 308. The CPF #2 322 in the CP Functionalities 314 may alsoauthenticate the WTRU 302 for the Core Network Instance #2 310.

A set of U-Plane functions (i.e. NS-1 UPF #1 326, NS-1 UPF #2 328, NS-1UPF #3 330 in the Core Network Instance #1 308, and NS-2 UPF #1 332,NS-2 UPF #2 334, NS-2 UPF #3 336 in the Core Network Instance #2) may beresponsible for providing a specific service to the WTRU 302. The set ofU-Plane functions above may also responsible for transporting U-Planedata of the specific service to the WTRU 302. For example, the NS-1 UPS#1 326 in the Core Network Instance #1 308 may provide an enhancedmobile broadband service to the WTRU 302, whereas the NS-2 UPF #2 334 inthe Core Network Instance #2 310 may provide a critical communicationservice to the WTRU 302.

When the WTRU 302 first connects to an operator's network through theRAN 304, a default core network instance that matches to the WTRU 302usage type may be assigned to the WTRU 302. The assigned default corenetwork instance may be the Core Network Instance #1 or Core NetworkInstance #2 depending on the WTRU 302 usage type. The WTRU 302 may havemultiple U-Plane connections to different sets of U-Plane functions thatare available at different core network instances simultaneously. Thismeans that the WTRU 302 may be connected to user plane functions NS-1UPF #1 326, NS-1 UPF #2 328, NS-1 UPF #3 330 in the UP Functionalities312, and at the same time, the WTRU 302 may be connected to another userplane functions NS-2 UPF #1 332, NS-2 UPF #2 334, NS-2 UPF #3 336 in theUP Functionalities 316. Although it is not shown in FIG. 3, theconnection to user plane functions may not be limited to the UPFunctionalities 312 and UP Functionalities 316. The WTRU 302 may havemultiple user plane connections to different user plane functions incore network instances other than the Core Network Instance #1 and CoreNetwork Instance #2.

The Core Network Selection Function (CNSF) 306 may be responsible forselecting a core network instance among the Core Network Instance #1 andCore Network Instance #2. The CNSF 306 may determine the core networkslice selection based on WTRU's 302 subscription and specific parameterssuch as WTRU 302 usage types. The CNSF 306 may also be responsible forselecting control plane functions within the selected core networkinstance that a base station may communicate with. For example, the CNSF306 may select CPF #2 322 and CPF #3 324 in the Core Network Instance #1308 to communicate with a base station. The selection of control planefunctions may be done by using specific parameters such as WTRU 302usage types. The CNSF 306 may be responsible for selecting a set of userplane functions that a base station may establish in the connection fortransporting user plane data of different services. For example, theCNSF 306 may select NS-1 UPF #2 328 in the Core Network Instance #1 308to transport user plane data of an enhanced mobile broadband service.The selection of user plane functions among NS-1 UPF #1 326, NS-1 UPF #2328, NS-1 UPF #3 330, NS-2 UPF #1 332, NS-2 UPF #2 334, and NS-2 UPF #3336 may be done by using specific parameters such as WTRU 302 usagetypes, service types and the like. Although it is not shown in FIG. 3,the selection of user plane functions may not be limited to the CoreNetwork Instance #1 and Core Network Instance #2 and the CNSF 306 mayselect other user functions located in core network instances other thanCore Network Instance #1 and Core Network Instance #2.

Referring now to FIG. 4, an example of network slice selection perservice provided by a network is illustrated. The slice selection androuting function 406 may be provided by the RAN 404, which may besimilar to a conventional NAS node selection function. Alternatively, aCN-provided function may perform that task. The slice selection androuting function 406 may route signaling to CN instances such as GeneralCN Instance A 408, General CN Instance B 410, Other CN Instance N 411,NB CN Instance A 412, and NB CN Instance B 414, based on WTRU-provided401 information, CN-provided information, or the similar.

All network instances of the PLMN 402 may share radio access, and theremay be a need for separating any access barring and (over)load controlper slice. This may be accomplished by conventional methods of separatedaccess barring and (over)load control, which is provided per PLMNoperator for network sharing. Using this method, there may be CNresources such as transport network resources that cannot be fullyseparated. For example, the General CN Instance A 408 and General CNInstance B 410 may have control plane and user plane functions as theirnetwork functions. For example, the General CN Instance A 408 mayinclude NF1 416 and NF2 418 for its control plane functions and NF3 420for its user plane function for Data Network 1 436. Similarly, theGeneral CN Instance B 410 may include NF1 422 and NF2 424 for itscontrol plane functions and NF3 426 for its user plane function for DataNetwork 2 438. Using the NF1 s 416 422, NF2 s 418 424, and NF3 s 420426, the General CN Instance A 408 and General CN Instance B may providefull core network functions to the WTRU 401.

The NF1 428 and NF3 430 in Narrowband (NB) CN Instance A 412 may providea narrowband service for the WTRU 401 for Data Network 3 440. Similarly,NF1 432 and NF3 434 in Narrowband (NB) CN Instance B 414 may provideanother narrowband service to the WTRU 401 for Data Network 4 442. Thenarrow band services may be an Internet of Things (IoT) services. Inthis case, the WTRU 401 may be an IoT device. Since an IoT service doesnot require a full core network functionalities, the NB CN Instance A412 and NB CN Instance B 414 may include fewer number of networkfunctions than the General CN Instance A 408 and General CN Instance B410 may include. This means that, in order to provide narrowbandservices, the NB CN Instance A 412 and NB CN Instance B 414 do not needto include NF2 s as the General CN Instance A 408 and General CNInstance B 410 do.

Referring now to FIG. 5, an example of network slice selection based ona multi-dimensional descriptor is shown. The embodiment shown in FIG. 5may use a multi-dimensional descriptor for network slice selection. Inorder to perform the network slice selection, the selection principlemay enable the appropriate selection function to deliver a certainservice even within a class of functions designed for a certain usecase. In other words, based on selection criteria, a correct networkslice and correct network functions within the network slice may beassigned to applications running in WTRUs 502, 504, 506 for networkservices that the applications require. The applications running inWTRUs 502, 504, 506 can provide multi-dimensional descriptors. Suchmulti-dimensional descriptors may contain an application ID, servicedescriptor (e.g., enhanced mobile broadband service, criticalcommunications, or massive machine type communications), and the like.

As described above, in order to choose the appropriate network slice andnetwork functions, a network may use a multi-dimensional descriptoralong with other information (e.g., WTRU's subscription) available inthe network. This may be referred to as a multi-dimensional selectionmechanism. The following may be possible options to select networkslices and functions based on a multi-dimensional descriptor. A firstoption may be a two-step selection mechanism. Along with information(e.g., WTRU's subscription) available in a network, a selection function507 in a RAN 508 may use an application ID (part of themulti-dimensional descriptor) to select an appropriate core networkslice among CN Slice A 510, CN Slice B 512, and CN Slice C 514. Theselection function 507, then, may use a service descriptor (part of themulti-dimensional descriptor) to select appropriate network functionswithin the selected network slice. Alternatively, a core networkselection function 505 may use the application ID to select anappropriate core network slice among CN Slice A 510, CN Slice B 512, andCN Slice C 514. The core network selection function 505, then, may use aservice descriptor to select appropriate network functions within theselected network slice.

In an embodiment, a WTRU1 502 may run an application that requires anenhanced mobile broadband such as 4K/8K UHD and Hologram. Theapplication may transmit its multi-dimensional descriptor to a RAN 508along with its application ID. In this case, the multi-dimensionaldescriptor may include the enhanced mobile broadband for its servicedescriptor. A selection function 507 in the RAN 508 may use theapplication ID to select CN Slice A 510 that provides the enhancedmobile broadband service for its appropriate core network slice. Afterthat, the selection function 507 in the RAN 508 may use a servicedescriptor (i.e. enhanced mobile broadband) to select MM1 516, SM1 522,and PC1 528. MM1 516 in the CN Slice A 510 may provide mobilitymanagement functions for the WTRU1 502 among all the mobility managementfunctions (i.e. MM1 516, MM2 518, MM3 520). SM1 522 and PC1 528 mayprovide appropriate session management and packet core functions for theenhanced mobile broadband service among all the session management (i.e.SM1 522, SM2 524, SM3 526) and packet core functions (i.e. PC1 528, PC2530, PC3 532) in the CN Slice A 510. Thus, the selection function 507 inthe RAN 508 may select the MM1 516, SM1 522, and PC1 528 as theappropriate network functions to provide the enhanced mobile broadbandservice.

In another embodiment, the WTRU2 504 may run an application thatrequires critical communications such as motion control, autonomousdriving, and factory automation. As described above, the applicationthat runs a critical communication service may transmit itsmulti-dimensional descriptor to a RAN 508 along with its application ID.The multi-dimensional descriptor may include critical communications forits service descriptor. A selection function 508 in the RAN 508 may usethe application ID to select a CN Slice B 512 that provides a criticalcommunication service for its appropriate core network slice. Afterthat, the selection function 507 in the RAN 508 may use the servicedescriptor, the critical communications, to select MM3 538, SM3 544, andPC3 550. MM3 538 in the CN Slice B 512 may provide mobility managementfunctions for the WTRU2 504, among all the mobility management functionsMM1 534, MM2 536, MM3 538. SM3 544 and PC3 550 may provide appropriatesession management and packet core functions for the criticalcommunication service among all the session management SM1 540, SM2 542,SM3 544 and packet core functions PC1 546, PC2 548, PC3 550. Thus, theselection function 507 in the RAN 508 may select the MM3 538, SM3 544,and PC3 550 for the critical communications service.

In another embodiment, the WTRU3 506 may run an application thatrequires massive machine type communications such as sensor network. Asdescribed above, the application that runs massive machine typecommunication service may transmit its multi-dimensional descriptor to aRAN 508 along with its application ID. The multi-dimensional descriptormay include massive machine type communications for its servicedescriptor. A selection function 507 in the RAN 508 may use theapplication ID to select a CN Slice C 514 that provides a massivemachine type communication service for its appropriate core networkslice. After that, the selection function 507 in the RAN 508 may use theservice descriptor, the massive machine type communications, to selectSM2 558, and PC2 564. In this embodiment, the WTRU3 506 may be an IoTdevice such as a sensor. Because IoT devices does not require full corenetwork functions like in the CN Slice A 510 and CM Slice B 512, the CNSlice C 514 may include fewer number of mobility management functions(i.e. MM1 552 and MM3 554) than the CN Slice A 510 and CN Slice B 512include (i.e. MM1 516, 534, MM2 518, 536, MM3 520, 538). In addition,the WTRU3 506 may not need to connect a mobility management function toreceive the massive machine type communication service. Thus, the CMSlice C 514 may not need to provide MM1 552 and MM3 554 to the WTRU 506for the massive machine type communication service. The SM2 558 and PC2564 in the CN Slice C 514 may provide appropriate session management andpacket core functions for the massive machine type communication serviceamong all the session management and packet core functions (i.e. SM1556, SM2 558, SM3 560, PC1 562, PC2 564, and PC3 566). Thus, theselection function 507 in the RAN 508 may choose the SM2 558 and PC2 564for the massive machine type communication service.

Another option may be a one-step selection mechanism. Along withinformation (e.g., WTRU's subscription information) available in anetwork, a selection function 507 within a RAN 508 or a selectionfunction 505 in a core network may use an application ID and a servicedescriptor (e.g., the multi-dimensional descriptor) to select anappropriate network slice and its respective network functions in CNSlice A 510, CN Slice B 512, and CN Slice C 514. It may then direct theWTRUs 502, 504, 506 to the selected network slice and functionsaccordingly.

As described above, various embodiments of how CP and UP functions canbe grouped per slice or across slices are illustrated in FIGS. 2A, 2B,2C, 3, 4, and 5. However, specific CP and UP functions may need to befurther described. The impact on a 5G communication system, as a resultof sharing such functions, may also need to be considered. For example,if paging is a shared network function among different network slices,then it needs to be described how network slices use or trigger theshared paging function to send a page to a WTRU. Conversely, if pagingis not a shared network function, then it needs to be described how eachnetwork slice can send paging messages to a WTRU. If each network slicesends paging messages to each of WTRU separately, there may be a need touse one or more identities for the WTRU.

There may be particular network services that require different networkfunctions performed by different CP and/or UP nodes. For example, in a5G system, a device or a WTRU may send IP and/or non-IP data. The non-IPdata can take two forms: non-IP PDUs and Ethernet frames. Furthermore,the transport requirement for IP vs non-IP data may be different.Specifically, the type of data that a network supports and transportsmay have an impact on a network slice selection because different CP andUP functions are required to support the type of data that a WTRUtransmits. Another type of data that a network may support isInformation Centric Networking (ICN) data, where a different networkslice can be used to transport such ICN type data. Embodiments describedherein may handle different data support by using independent networkslices.

As described above, grouping CP nodes in an independent network slice oras shared functions across network slices, is a high level design.Embodiments how CP nodes and functions operate may need to be furtherdescribed. More specifically, embodiments such as which nodes performauthentication and paging may need to be listed. More importantly, theimpacts on a 5G system by performing actions, for example, paging in anindependent or shared node, may also need to be described in detail.

In addition, other embodiments that describe a proper selection of anetwork function after a network slice is assigned may need to beaddressed. For example, where a slice comprises a shared CP and anindependent UP node, after a WTRU is assigned to receive services fromtwo different network slices that have independent UP nodes, theselection of a correct UP node (i.e., how data will be forwarded to thecorrect UP node) may need to be addressed.

Additionally, a location of a responsible node for authentication,authorization, and identification may need to be described. As shown inFIG. 2B, there may be several questions about “where” certain importantsecurity functions may reside. If an operator would like to have acentralized control plane management, a “Shared CN CP Functions 210” maytake the registration of WTRU 202. Therefore, this Shared CN CP 210 nodemay be responsible for authentication as well as identity management. Inresponse to the authentication process performed by the Shared CN CPFunctions 210, how the CN instance slice #1 212 and CN instance slice #2214 use the authentication information and how the authenticationinformation maps the WTRU 202 identities (e.g. an external ID) to oldidentities within a network may need to be addressed.

Handling of a network slice in a multi access network (AN) environment,such as 3GPP and non-3GPP access network, may need to be addressed. Theembodiments described above may address cases where the AN correspondsto a 3GPP-based AN. However, 5G systems may include both 3GPP andNon-3GPP access networks. Thus, a 5G system should consider all allowedtypes of access networks when it manages network slices.

Delayed network slice selection may need to be addressed in certainscenarios. Such a scenario where a network may not select a networkslice at initial registration or attach may be illustrated in FIG. 2B.For example, a WTRU 202 may register to shared CN CP functions 210. Anetwork slice may then be selected when there is a need to use aparticular function from non-shared CP functions in CN Instance #1 212and CN Instance #2 214. As a result, a network slice selection may takeplace to utilize the particular non-shared CP functions. Such proceduresmay need to be detailed, especially with respect to how and which nodesare responsible for the network slice selection.

Referring now to FIG. 6, a diagram illustrating an overall architecturefor network slicing per data types is shown. As described above,different network slices may be used for different data types that aresupported by WTRUs 602, 604, 606. In a 5G system, a network slice maysupport both IP and non-IP data type. A network slice can be used tocarry IP data, and another network slice can be used to carry non-IPdata. This may be referred to as a network slice per data type. Inaddition to the IP and non-IP data type, a network slice may carrydifferent non-IP data types. This means, a network slice can be used tocarry non-IP PDU data and another network slice can be used to carryEthernet frames. This may be referred to as a network slice per non-IPdata type. Although the non-IP data may refer to both non-IP PDU andEthernet frames, in some embodiments these types of non-IP data may beconsidered to be different.

FIG. 6 shows an example with three network slices (i.e. Network Slice #1610, Network Slice #2 612, and Network Slice #3 614) to service andtransport different data types. These network slices, Network Slice #1610, Network Slice #2 612, and Network Slice #3 614, may share a set ofCP functions referred to as “Shared CP 616.” Each of Network Slice #1610, Network Slice #2 612, and Network Slice #3 614 may have their ownindependent/isolated set of CP functions referred to as “Non-Shared CP#,” where “#” may refer to the slice ID at least within the CN (i.e.Non-Shared CP1 618, Non-Shared CP2 620, or Non-Shared CP3 622). In thisexample, the Network Slice #1 610, Network Slice #2 612, and NetworkSlice #3 614 may carry a specific data type, such as IP data type,non-IP data type (e.g., non-IP PDU and/or Ethernet Frames), or data typerelated to Information-centric Networking (ICN). The ICN data may alsobe non-IP data, IP data that encapsulates ICN PDUs, or other forms oftransporting ICN PDUs.

The Non-Shared CP1 618, Non-Shared CP2 620, and Non-Shared CP3 622 mayalso have interfaces 624, 626, 628 with a main or share CP function 616,respectively. As shown in FIG. 6, WTRUs 602, 604, 606 may have access630, 632, 634, 636 to Network Slice #1 610, Network Slice #2 612, andNetwork Slice #3 614. For example, WTRU Z 606 may have access 634 toNetwork Slice #1 610 for IP data. The WTRU Z 606 may have access 636 toNetwork Slice #3 614 for non-IP data. The WTRU X 602 may have access 630to Network Slice #1 610 for IP data. The WTRU Y 604 may have access 632to Network Slice #2 620 for ICN data.

Moreover, the WTRUs 602, 604, 606 may have direct access or interface638 with the shared CP 616 via the RAN 608, or indirect access orinterface via the Non-Shared CP1 618, Non-Shared CP2 620, and Non-SharedCP3. When an indirect access or interface is established, the access630, 632, 636 may be used to connect to the shared CP 616 via Non-SharedCP1 618, Non-Shared CP2 620, and Non-Shared CP3. For example, the WTRU X602 may be connected to the shared CP 616 via the Non-Shared CP1 618using the interface 630. The WTRU Y 604 may be connected to the sharedCP 616 via the Non-Shared CP2 620 using the interface 632. The WTRU Z606 may be connected to the shared CP 616 via the Non-Shared CP3 622using the interface 636. When a direct access or interface isestablished, the access 638 may be used to connect the WTRUs 602, 604,606 to the shared CP 616.

The WTRUs 602, 604, 606 may have direct contact or interface with theNon-Shared CP1 618, Non-Shared CP2 620, and Non-Shared CP3 in theNetwork Slice #1 610, Network Slice #2 612, and Network Slice #3 614.For example, when directly connected, the WTRU X 602 may have directaccess 630 to the Non-Shared CP1 618. The WTRU Y 604 may have directaccess 632 to the Non-Shared CP2 620. The WTRU Z 602 may have directaccess 636 to the Non-Shared CP3 622.

In addition, the WTRUs 602, 604, 606 may have indirect access orinterface to the Non-Shared CP1 618, Non-Shared CP2 620, and Non-SharedCP3 in the Network Slice #1 610, Network Slice #2 612, and Network Slice#3 614 via a shared CP node 616. When indirectly connected, the WTRU X602 may use the access 624 to the Non-Shared CP1 618 via the shared CP616. The WTRU Y 604 may use the access 626 to the Non-Shared CP2 620 viathe shared CP 616. The WTRU Z 606 may use the access 628 to theNon-Shared CP3 622 via the shared CP 616.

The following embodiments may include selection of a network slice basedon support or need for non-IP data. As explained above, the term “non-IPdata” may refer to all forms of non-IP data (e.g., non-IP PDU, EthernetFrames, ICN data, etc.) It is noted that the term “Non Access Stratum(NAS)” may be used to refer to higher layer messages above the radio,such as the conventional NAS protocol. However, NAS may be any otherprotocol that runs between WTRUs and CP functions in a CN and is notnecessarily limited to the conventional NAS protocol. The selection of anetwork slice for a WTRU can be done at a RAN or at a CN.

A WTRU may, upon establishing a radio connection, indicate that therequested service is non-IP data. This indication may be in any form,such as a capability or explicit service type, or it may be inferredfrom the WTRU type. The WTRU may also indicate the need or request fornon-IP service in any of its NAS messages that are either related tomobility or session management procedures.

A RAN may take this information or indication into account and mayselect a network slice that supports this service. The RAN node may thenforward the WTRU's higher layer message (e.g., NAS) to the CP functionin that network slice. Alternatively, the RAN may use other informationfrom the WTRU to perform the selection of the most appropriate CPfunction in the CN. The RAN may then send this information to the CPfunction.

The CP function in the CN may receive a message from the WTRU with anindication for non-IP data. The CP function may verify if the specifictype of non-IP data that is requested can be provided by the CPfunction. If the CP can provide service for non-IP data, it may continueto process the WTRU request. Otherwise, the CP function may redirect theWTRU message to another network slice using a Dedicated Core Network(DECOR) solution. This embodiment may assume that the CP function haslocal information or configuration to determine the network slice or theCP address within a network slice that can serve the WTRU for therequested service, in this case, non-IP data. When determining thetarget network slice to serve the WTRU for non-IP data, the current CPfunction may input the service type (i.e., in this case “non-IP data”)into its local look-up function.

In an embodiment, a WTRU may already be registered in the network for aparticular service (e.g., IP-data service or non-IP data). The WTRU maysupport service for a secondary data type, and as such, may want to getthe service. The WTRU may send a request to get a secondary service fora different data type which may be offered by another network slice. Themethods to achieve this such as when a WTRU may need to do so aredescribed herein.

When a WTRU needs to select a secondary service, one network slice mayprovide support for different services. For example, a network slice maybe deployed to provide connectivity for the Internet of Things (IoT),for which there may be different connection or transport modes. One IoTapplication may require an IP connection, while another may not if thedata is encapsulated in a control plane message. Thus, the generalservice type may be IoT; however the specific service can be “IP forIoT” or “Data over CP for IoT.”

Therefore, one network slice may actually be used to provide at leastthese two types of transports or connections for the WTRU. It istherefore important for the WTRU to know whether or not the same slicecan provide more than one service. If so, the WTRU needs to know whatthe services are provided by the network slice. This may help the WTRUto determine whether a new network slice has to be selected andregistered with, or if the WTRU can simply request the service from theexisting network slice. The following embodiments may address thisissue.

Referring now to FIGS. 7A and 7B, a signaling diagram illustrating anetwork slice selection for service supported by the network slice isshown. The WTRU 702 may transmit the Registration Request message 710 tothe CP function of the network. The Registration Request message 710 mayinclude a list of supported services or a list of services that the WTRU702 is capable to receive (hereinafter referred to as “supportedservices”). Alternatively, the WTRU 702 may simply request to beinformed of the list of services that the current network slice (or thecurrent CP within this slice) supports. This indication of supportedservices, or the solicitation of the network's supported services, maybe done or included in the Registration Request message 710 that is sentto the network.

If the WTRU 702 is already registered and it wants to determine whetheror not the network supports other services, the WTRU 702 may send a newcontrol message by, for example, NAS signaling or a Supported ServiceType Request message 714. In this Supported Service Type Request message714, the WTRU 702 may either indicate its supported and/or desiredservices, or it may solicit the network to provide the list of servicesthat are supported in the network.

The network (e.g., any CP node or NF in the network) may receive a NASmessage with a list of WTRU-supported services, or with a solicitationrequest to inform the WTRU 702 about the services that are supported inthe network. The network may verify if the WTRU's subscription allowssuch information to be provided to the WTRU 702, which may also be basedon the network policy. The network may determine to send a list ofsupported network services in the Supported Service Type Responsemessage 716 to the WTRU 702. The network may send a NAS message and mayindicate the supported services in the NAS message.

Alternatively, if the request from the WTRU 702 is for a specificservice, the network may send a response with a {service type, support}indication, where the “service type” reflects the particular serviceabout which network support is requested, and the “support” indicates ifthe service is supported or not. The network may send this list in anyNAS message, either as part of the registration process, or when theWTRU 702 sends any NAS message that contains such a request.

For a given network slice with which the WTRU 702 is registered, theWTRU 702 may save the supported services in that network slice asdetermined using the embodiments described above. When the WTRU 702requires or needs new services, the WTRU 702 may check the list ofsupported services in the network slice that the WTRU 702 is registered.If the service is indicated to be supported, then the WTRU 702 maysimply send a NAS message to request the service. The NAS message may besent to this network slice or to the CP/NF within the network slice towhich the WTRU 702 is registered. The lower layer messages (e.g., radiomessages) may contain a service indicator that points to this networkslice. This may ensure that the service request, or any NAS message thatmay be used to obtain a new service, may be sent to the appropriatenetwork slice (e.g., the network slice with which the WTRU 702 isalready registered).

On the other hand, if the WTRU 702 determines that the service needed isnot supported in the network slice, the WTRU 702 may then send anotherradio message 722 (e.g. RRC message). This radio message 722 mayencapsulate a NAS message for registration. The radio message 722 mayinclude a corresponding service descriptor associated with the Slice 2708, which can be in any format to indicate the desired service type.The RAN 704 or the slice selection function may use this parameter topick the appropriate network slice and may forward the NAS message 724to the selected network slice. It should be noted that the NASregistration message may be different from the NAS message used to get aservice within the same network slice. The selected network slice, theSlice 2 708 here, may send a Service Response message 726 to the WTRU702.

Thus, when a required service is supported in the current network slice,the WTRU 702 may send the Additional Service Request message 718. If theWTRU 702 needs to get the service from another network slice, the WTRU702 may then send a registration message to first register in thatnetwork. The WTRU 702 may ensure that the lower layer parameter (e.g.,dedicated core network type, “WTRU usage type,” “service descriptor,”etc.) reflects a different service type and/or a different network slicefrom that which the WTRU 702 is already registered.

The following embodiments may include a responsible node for securityfunctions and identity management in network slicing. In an embodiment,the “Shared CN CP Functions” may be responsible for the registration(e.g., Attach/TAU) procedure. A Registration (Attach/TAU) Requestmessage from a WTRU may terminate in Shared CN CP Functions. Thisregistration request message may contain important WTRU relatedparameters such as capabilities, (e)DRX parameters, PSM information orthe like.

At this point, depending on whether the WTRU uses IMSI or an alias foridentification purpose, the Shared CN CP Functions may retrieve WTRU'sIMSI number or the similar either by forcing the WTRU to send it (e.g.,through the Identification Procedure in NAS specs) or by simplyreceiving it from the previous anchor node (e.g., an MME, SGSN oranother Shared CN CP Functions) where the WTRU was registered. In orderto facilitate some of the following procedures, the Shared CN CPFunctions may, once the registration phase has succeeded and completed,send the IMSI number to the CN instance slice #1 and slice #2. This mayensure that both slices are made aware of the WTRU's IMSI number or thesimilar identification information.

Another important factor is that the WTRU may get its “temporary”number, whether it is a GUTI or S-TMSI, allocated from the Shared CN CPFunctions. With this mechanism, the slices may be hidden from the WTRU,which may believe that it is communicating with only one node, theShared CP node.

Upon reception of the “Registration Request” message, the Shared CN CPFunctions may contact the Home Subscriber Server (HSS) and ask forAuthentication Vectors. After receiving the vectors, the Shared CN CPFunctions may start an authentication procedure toward the WTRU based onthe current mechanisms. If the WTRU passes this phase, the Shared CN CPFunctions may send a message to both instance Slice #1 and Slice #2informing them that this WTRU has been successfully authenticated. Atthis point, both Slice #1 and Slice #2 may set flags in theircorresponding databases and consider the WTRU as completely “valid.” TheShared CN CP Functions may also start a Security Mode Control proceduretoward the WTRU and then pass security contexts to the Slice #1 andSlice #2 to be used for the User Plane security.

A shared RAN may only have a signaling connection to the Shared CN CPFunctions, so all communications, even between instance Slice #1/Slice#2 and the WTRU, may go through the Shared CN CP Functions. As anexample, if the instance Slice #1 has something to be sent to the WTRU,it may not need to know the state (e.g., idle/connected mode) of theWTRU. It may just send a request to the Shared CN CP Functions which, inturn, will page the WTRU and establish a signaling connection.

In another embodiment, a mechanism that combats denial of serviceattacks toward a WTRU may be included. A first authentication messagesent from Shared CN CP Functions to the WTRU may have a new parameter(e.g., a “token”) that is derived from the WTRU's IMSI number and RAND.After the authentication process is complete, the Shared CN CP Functionsmay pass this token to other network slices such as Slice #1 and Slice#2 for future use. If the operator's configuration is subject to dynamicchange in a way that the Slice #2 may, for example, take over bothControl and User Plane, then Slice #2 may include the “token” in thesubsequent NAS messages to the WTRU. These (subsequent) messages shallbe integrity protected even for the reject cases.

The WTRU may communicate with the Shared CN CP Functions. This meansthat the Shared CN CP Functions may be aware of any external ID that theWTRU may have. For that reason, the Slice #1 and Slice #2 may inform theShared CN CP Functions about any external ID that the WTRU is assignedor is using. The mapping between the external IDs, IMSI and thetemporary WTRU ID may be done in the Shared CN CP Functions. When theUser Plane bearers are established by the Shared CN CP Functions, theShared CN CP Functions may inform the corresponding entity of the usedidentities for User Plane connections.

The following embodiments may include split functionality management. Asshown in FIG. 2B, the load on Shared CN CP Functions 210 may increasedramatically based on the number of registered WTRUs and the number ofslices that are connected to the Shared CN CP Functions 210. In thefollowing embodiments, it may be assumed that a network operator hasconfigured their network according to the FIG. 3 (i.e., there are onlytwo CN instance slices connected to the Shared CN CP Functions). It mayalso be assumed that all IP traffic may reside in Core Network Instance#1 308 and all Non-IP traffic may be in Core Network Instance #2 310.

In order to decrease the load on the Shared CN CP Functions, the SharedCN CP Functions may handle “Mobility Management” portion of the chosenprotocol between a WTRU and a core network. As an example, assuming thatthe WTRU can send both Mobility Management (MM) and Session Management(SM) messages in a secured way, the Shared CN CP Functions may deal withthe MM messages.

Accordingly, the MM messages may terminate in the Shared CN CPFunctions. The SM messages may be passed by the Shared CN CP Functionsto either Slice #1 or Slice #2. As previously stated, Slice #1 may bethe terminating node for IP traffic and Slice #2 may be the terminatingnode for the Non-IP traffic

The following embodiments may distinguish between network slices and therouting of data under the assumption that a WTRU has a short packet tosend and a network is configured to allow the WTRU to send its data,whether it is IP or Non-IP, over Control Plane.

In an embodiment, a new protocol layer (in-line with the SessionManagement) may be used to transfer all Non-IP related data. When a WTRUneeds to send a short Non-IP packet over the control plane, it maypiggy-back the packet in this new protocol message format and maytransmit to the Shared CN CP Functions. At the Shared CN CP Functions,the message may be integrity checked and the content of the message,which may be the short Non-IP packet, may be extracted to be forwardedto the Slice #2 using appropriate protocol on that interface. Thedeciphering of the packet may be done in the Shared CN CP Functions.However, to ease the functionality and decrease the load, thedeciphering may be performed at the Slice #2.

As for the IP-packets, the WTRU may simply piggy-back them onto certainSM messages and may send them to the Shared CN CP Functions. The SharedCN CP Functions may perform an integrity check on the message. Afterthat, the Shared CN CP Function may extract the IP-Packet and send it toSlice #1. The ciphering/deciphering options may be the same as thosediscussed above. It should be noted that if the ciphering/deciphering isto take place in the slices, the Shared CN CP Functions may have to passthe Ciphering Keys as well as Algorithms to the slices.

In another embodiment, in the MM and SM protocol discussed above,certain SM messages may be used to carry both IP and Non-IP packets overthe Control Plane. The SM message may be piggy-backed onto the MMmessage. In this example, the WTRU may send an indication, preferably inthe MM message, to the Shared CN CP Function. The indication may informthe Shared CN CP Functions that the message is carrying a SM message andwhether the content of the message (i.e., the piggy-backed data) is IPor Non-IP. Using this indication, the Shared CN CP Functions may knowwhich node is to be the actual recipient of the packet. As discussedabove, the Shared CN CP Functions may check the integrity of the messagefirst. The ciphering/deciphering may follow the same mechanism asdiscussed above. One major difference is that both Slice #1 and Slice #2may support the SM protocol.

Referring now to FIG. 8, a signaling diagram illustrating a dedicatedslice selection at a shared CP node is shown. A Shared CP 806 mayprovide a WTRU 802 access to a Dedicated Slice 808 for a specificservice provided by the Dedicated Slice 808. The WTRU 802 may transmit aNAS message 810 (e.g. registration request) that indicates a request toestablish a connection for the specific service. As described above, theNAS message 810 may include MM messages and SM messages. The NAS messagemay include a user date type indication that indicates an IP data ornon-IP data. A RAN 804 may have a signaling connection to the Shared CP806, so all communications may go through the Shared CP 806. Uponreceiving the NAS message 810, the Shared CP 806 may authenticate theWTRU 802 using authentication function in the shared CP network function(NF) at step 812.

If the WTRU 802 is successfully authenticated, at step 814, the SharedCP 806 may select, based on the user data type indication in the NASmessage 810, a Dedicated Slice 808 for the specific service. Uponselecting the Dedicated Slice 808, the Shared CP 806 may determine thetype of the NAS message 802 (e.g. MM and/or SM) based on the user dataindication at step 816, and read MM messages at step 816. The Shared CP806 then passes SM messages 820 to the Dedicated Slice 808 along withthe authentication token at step 818. Specifically, the Shared CP NF mayread the MM messages and send the SM messages 820 to the CP of DedicatedSlice 808. This means that all MM messages may terminate in the Shard CPNF. However, the SM messages may simply be passed to the dedicatednetwork slices by the Shared CP NF.

Upon receiving the SM message with the authentication token 820, theDedicated Slice 808 may transmit the SM response message 822 to theShared CP 806 to establish a communication link between the WTRU 802 andthe Dedicated Slice 808. The Shared CP 806 may combine the SM responsemessage 822 with MM response message, and then send the NAS responsemessage 824 to the WTRU 802.

The Shared CP 806 may select the Dedicated Slice 808 based on whetherthe attached request message is for the transmission of the controlplane data or an IP connection. The Shared CP 806 may provide anauthentication token to the selected Dedicated Slice 808 as anindication of authentication by the Shared CP NF. The Shared CP 806 mayconnect the WTRU 802 to the Dedicated Slice 808 to provide the specificservice. Thus, the control plane of the WTRU 802 may be connected to theDedicated Slice 808 through the Shared CP 806.

The following embodiments may include multi-access networks and networkslice management. Based on the multi-dimensional descriptor describedabove, a WTRU may provide a descriptor or template to indicateparameters such as the type of service requested from the network. Whenthe request is received through either a TWAN or an ePDG (hereinafterreferred to as a “Non-3GPP Access Gateway” or “N3AGW”), the N3AGW mayeither perform Slice Selection based on the descriptor, or it mayforward the request to a CN Slice Selection Node, such as a Central CPentity or even a 3GPP Access Network entity (e.g., a next generationeNB). This node may be a logical node that can be connected to one ormore non-3GPP access points. This node may be pre-configured withinformation such that it can select the appropriate network slices ornodes to match the WTRU's provided service descriptor. This node maycontain a mapping between a service descriptor and a network slice orCP/NF associated with a network slice.

The WTRU may include a SSID, a Network Service ID, or an Application IDthat may be used to select a particular N3AGW. The WTRU may use networkidentifiers that are known or broadcast over the air (e.g., SSID) orthrough a L2 advertisement protocol (e.g., the Generic AdvertisementProtocol of 802.11u) to select an AP that is known to connect to networkwith a particular service type (and hence slice) to connect to a N3AGW.

The selection of a particular network may allow the WTRU to identifynetworks that are capable of performing Slice Selection Functions. TheWTRU may use an APN to signal to the N3AGW Network Nodes that arecapable of performing Network Slice Selection. For example, theinformation provided by the WTRU may lead to the selection of aparticular CP Entity that is capable of performing network sliceselection. A WTRU may include the required service descriptor in the L2MAC frame of a non-3GPP access technology.

The Network Slice Selection function may use parameters provided in thedescriptor to determine whether the N3AGW is capable of supporting theservices requested by the WTRU. If the N3AGW satisfies the requirementsof the particular service specified in the descriptor, a CP Entity mayproceeds with the selection of other CN specific functions. This maydepend on other aspects of the descriptor as well as aspects of thesubscriber information. Otherwise, the CP entity may choose to directthe WTRU to reselect to a different AN (e.g., both 3GPP and Non-3GPPbased). The CP entity may choose a particular AN for the WTRU or mayinstruct the WTRU to perform selection of a new AN altogether.

The following description may address delayed network slice selection.As described above, a shared CP function may contain mobility managementfunctionalities, whereas non-shared CP functions in various slices maycontain session management functionalities. Accordingly, when a WTRUinitially registers (i.e., attaches) with a network, which is a mobilitymanagement event, the WTRU may interact with the shared CP for mobilitymanagement. The network may not select the network slice at initialregistration if the network does not need to select or use CP functionsfrom the shared CP in different slices.

At the registration phase, however, the network may send information tothe WTRU about possible network slices with which the WTRU is authorizedto connect. As described above, the shared CP function may send theinformation about possible network slices based on WTRU capabilityand/or service type along with subscription information from thesubscription database (i.e., similar to HSS). The WTRU may use theinformation during session management procedures with the network (e.g.,PDU connection request).

A network slice may be selected during the session management (SM)procedure, which may include PDU connection establishment. During the SMprocedure, the WTRU may include slice information that was previouslyreceived during attach procedure. With that network slice information,the WTRU may assist the shared CP function to select a slice or todirect the WTRU's SM request to the appropriate network slice. Thenetwork slice selection function may either be part of the RAN or theshared CP function. In either case, the session management may bedirected to the appropriate slice.

The network slice selection function may consider the information in theSM message and make a decision to route (re-direct) the message to thenetwork slice that can best meet the WTRU's session requirements. Theinformation may include PDU connection type (IP vs. Non-IP), IP version(IPv4 or IPv6), application information (app ID), required quality ofservice, the network slice information received duringattach/registration procedure, and the like.

Referring now to FIG. 9, a diagram illustrating network slice selectionwhen there is a session management request is shown. A PDU connectionrequest may be an example of the SM procedure shown in FIG. 9. Thisprocedure may extend to other SM call flows.

At step 909, the WTRU 902 may be attached to a non-shared CP but thereis no network slice selected for the shared CP. The WTRU 902 may sendthe PDU connection request 910 to the Shared CP 906. The message mayinclude one or more of the following parameters: connection type (IP vs.Non-IP), IP version (IPv4 or IPv6), application information (app ID),required quality of service (including but not limited to QCI value,priority, and required bit rate), the slice information (slice ID, typeof slice such as enhance mobile broadband, mIoT, criticalcommunications, etc.), Data Network name (similar to APN), and the like.

Upon receiving the PDU connection request 910, the Network SliceSelection Function in the Shared CP 906 may select a network slice basedon the received parameters at step 911. Additional parameters may beused with the received parameters. Such additional parameters mayinclude network configuration/local policy, and WTRU/user subscriptioninformation, which may either be received by the CP node during theinitial attach procedure or during the network slice selectionprocedure. The Shared CP 906 may also consider congestion level of thecontrol plane and user plane when it performs the slice selectiondetermination.

The Shared CP 906 may forward the PDU connection request message 912 tothe CP Slice #1 908, which is the non-shared CP function of the selectednetwork slice. The non-shared CP function at the CP Slice 1 908 mayexecute the SM procedure and set up user plane connection based on theparameters received from the WTRU 902 at step 913. The non-shard CPfunction may transmit a PDU connection accept message 914 to the sharedCP function at the Shared CP 906. After that, the PDU connection acceptmessage 916 may be forwarded to the WTRU 902 via interface (similar toNAS) between the shared CP 906 and the WTRU 902.

The PDU connection accept message 916 may include information about theselected network slice for either the base station or the WTRU 902. Thebase station may route user plane messages to the appropriate networkslice. The WTRU 902 may route the user plane data and other followingcontrol message (e.g., SM messages) to the selected network slice atstep 918. Once the WTRU 902 is aware of the selected network slice, thedata may be sent to the UP functions of the selected network slice.

In an embodiment, multiple network slices may be selected by the SharedCP 906 if the WTRU 902 sends another PDU connection request to theshared CP function based on the aforementioned parameters and thecharacteristics of the required data connection.

Referring now to FIG. 10, a diagram illustrating an example procedurefor providing access to dedicated network slices in a shared CP networkfunction (NF) is shown. At step 1002, the shared CP NF in the shared CPnode may receive a NAS message from a WTRU. As described above, the NASmessage may include a MM message and a SM message. The MM message mayinclude a registration request that indicates a request to establish acommunication link between the WTRU and a dedicated network slice forthe specific service that is provided by the dedicated network slice.The NAS message may also include a user data type indication thatindicates an Internet Protocol (IP) data and a non-IP data. The non-IPdata may include a non-IP Protocol Data Unit (PDU), an Ethernet frame,an Information Centric Network (ICN) data, or the like.

Upon receiving the NAS message, the shared CP NF may initiate anauthentication function in the shared CP NF to authenticate the WTRU atstep 1004. If the WTRU is successfully authenticated, the shared CP NFmay generate an authentication token for the security and identitymanagement at step 1006. At step 1008, the shared CP NF may select anetwork slice among multiple network slices for a user plane (UP)service provided by the network slice. The shared CP NF may select thenetwork slice based on the user data type indication. The selectednetwork slice may be a dedicated network slice to provide the UP serviceto the WTRU. At step 1010, the shared CP NF may determine a type of NASmessage based on the user date type indication included in the NASmessage.

After determining the type of NAS message, for example, MM or SM, theshared CP NF may transmit the SM part of the message to the non-sharedCP NF in the selected network slice along with the authentication tokenat step 1012. The SM message may indicate the UP service provided by theselected network slice. At step 1014, the shared CP NF may receive a SMresponse message from the non-shared CP NF. The SM response message mayindicate whether the selected network slice may provide the UP serviceor not. If the selected network slice provides the UP service, theshared CP NF may transmit a NAS response message that includes both MMand SM part to the WTRU to establish the communication link between theselected network slice and the WTRU for the UP service. The NAS responsemessage transmitted from the shared CP NF may include the SM responsereceived from the non-shared CP NF.

Although features and elements are described above in particularcombinations, one of ordinary skill in the art will appreciate that eachfeature or element can be used alone or in any combination with theother features and elements. In addition, the methods described hereinmay be implemented in a computer program, software, or firmwareincorporated in a computer-readable medium for execution by a computeror processor. Examples of computer-readable media include electronicsignals (transmitted over wired or wireless connections) andcomputer-readable storage media. Examples of computer-readable storagemedia include, but are not limited to, a read only memory (ROM), arandom access memory (RAM), a register, cache memory, semiconductormemory devices, magnetic media such as internal hard disks and removabledisks, magneto-optical media, and optical media such as CD-ROM disks,and digital versatile disks (DVDs). A processor in association withsoftware may be used to implement a radio frequency transceiver for usein a WTRU, UE, terminal, base station, RNC, or any host computer.

What is claimed is:
 1. A method for providing access to a network slice,the method comprising: receiving, at a network node performing mobilitymanagement (MM) control plane functionalities, a Non-Access Stratum(NAS) message being an MM message, wherein the MM message includes asession management (SM) message for a protocol data unit (PDU) sessionassociated with the network slice; and transmitting, to a network nodeperforming SM control plane functionalities associated with the networkslice, the SM message that indicates a user plane (UP) service providedby the PDU session associated with the network slice.
 2. The method ofclaim 1, wherein the MM message includes a registration request toestablish a communication link between a wireless transmit/receive unit(WTRU) and the network slice.
 3. The method of claim 2, furthercomprising: authenticating the WTRU based on the MM message; generatingan authentication token on a condition that the WTRU is successfullyauthenticated; and transmitting the authentication token to the networknode performing the SM control plane functionalities associated with thenetwork slice.
 4. The method of claim 3, wherein the authenticationtoken is generated based on the WTRU's identification information. 5.The method of claim 1, further comprising receiving, from the networknode performing the SM control plane functionalities, an SM responsemessage that indicates whether the network slice provides the UPservice.
 6. The method of claim 1, wherein the NAS message includes auser data type indication that indicates an Internet Protocol (IP) dataand a non-IP data.
 7. The method of claim 6, wherein the non-IP datacomprises a non-IP Protocol Data Unit (PDU), an Ethernet frame, andInformation Centric Network (ICN) data.
 8. The method of claim 6,further comprising: determining a type of the NAS message based on theuser data type indication; and transmitting, to the network nodeperforming the SM control plane functionalities, the SM message based onthe type of the NAS message.
 9. The method of claim 6, furthercomprising selecting, based on the user data type indication, thenetwork slice among a plurality of network slices.
 10. A first networknode comprising: a processor; a receiver; and a transmitter, theprocessor and the receiver configured to receive, at the first networknode performing mobility management (MM) control plane functionalities,a Non-Access Stratum (NAS) message being an MM message, wherein the MMmessage includes a session management (SM) message for a protocol dataunit (PDU) session associated with a network slice; and the processorand the transmitter configured to transmit, to a second network nodeperforming SM control plane functionalities associated with the networkslice, the SM message that indicates a user plane (UP) service providedby the PDU session associated with the network slice.
 11. The firstnetwork node of claim 10, wherein the MM message includes a registrationrequest to establish a communication link between a wirelesstransmit/receive unit (WTRU) and the first network node performing theMM control plane functionalities.
 12. The first network node of claim11, wherein the processor is configured to: authenticate the WTRU basedon the MM message; and generate an authentication token on a conditionthat the WTRU is successfully authenticated, wherein the processor andthe transmitter are further configured to transmit the authenticationtoken to the second network node performing the SM control planefunctionalities associated with the network slice.
 13. The first networknode of claim 12, wherein the authentication token is generated based onthe WTRU's identification information.
 14. The first network node ofclaim 10, wherein the processor and the receiver are further configuredto receive, from the second network node performing the SM control planefunctionalities, an SM response message that indicates whether thenetwork slice provides the UP service.
 15. The first network node ofclaim 10, wherein the NAS message includes a user data type indicationthat indicates an Internet Protocol (IP) data and a non-IP data.
 16. Thefirst network node of claim 15, wherein the non-IP data comprises anon-IP Protocol Data Unit (PDU), an Ethernet frame, and InformationCentric Network (ICN) data.
 17. The first network node of claim 15,wherein the processor configured to: determine a type of the NAS messagebased on the user data type indication, wherein the processor and thetransmitter are further configured to transmit, to the second networknode performing the SM control plane functionalities, the SM messagebased on the type of the NAS message.
 18. The first network node ofclaim 17, wherein the processor is further configured to select, basedon the user data type indication, the network slice among a plurality ofnetwork slices.
 19. The first network node of claim 10, wherein thefirst network node is a control plane (CP) network function (CP NF) thatperforms the MM control plane functionalities and the second networknode is a CP NF performing the SM control plane functionalities.
 20. Thefirst network node of claim 19, wherein the CP NF performing the MMfunctionalities and the CP NF performing the SM functionalities arelogically isolated in a network node.